We develop circular exponential amplification reaction (EXPAR)-based surface-enhanced Raman spectroscopy (SERS) for simultaneous sensitive detection of multiple microRNAs in non-small cell lung cancer cells. This method possesses distinct advantages of excellent selectivity and high sensitivity with a detection limit of as low as 0.5 fM, which has improved by as much as 6 orders of magnitude as compared with the previously reported SERS-based direct assay.

National Natural Science Foundation of China
; Award for the Hundred Talent Program of the Chinese Academy of Sciences
; Fund for Shenzhen Engineering Laboratory of Single-molecule Detection and Instrument Development
; State Ministry of Health of China
; Peking University Third Hospital